Dental casting-machine.



D. PERRY,

umm www; Momma APPLICAUGN FILM* JMJ.

lessees.

application filed; January i wherein the revolving element rotates in a horizontal plane. One ol the objects ot' my invention is to provide a machine extrcn'lely simple in construction. avoiding all the usual adjust-ment screws and machined parts, and still retain with increased practicability, certain salient features desirable in the art..

A further object is to provide a machine, economic in its usage. whereby a saving ot' heat and of material used in preparing the molds, and material to be cast therein, is effected.

The invention consists in the constructiomrmnbination and arrangement of parts illustrated in the drawings and described in the specification of which the drawings form apart.'

Referring tothe drawings,

Figure 1 is a perspective-view of the een tritugal castingl mechanism of a dental cast-` ingq machine,

vFig. 2 is a side View of the same partly in section.

Fig. and

Fig. el is a sectional fragmentary view of details.

Fig. 5 is a sectional side view of a mold.

3 is a section. on line 1 1 ot Fig. l,

the actuatingr element element not being showin.

'The rot-atingclement comprises a crossbeam 2, shaped at one of its outer ends to r said centrifugal.

4'form a semi-cylindrical mold ring cradle 3 the cross-beam Q.

Spccii'ieatien of Letters tent.

.i auxiliary cradles, the rings and auxiliary In the drawings, Fig. l represents the cenf tritugal element of a denti l casting machine,

Patented @en latam.

a, lele. 'sensi ai. erica/i.

with a reservoir l0 and a discharge opening 1l, the Crucible support being arranged so that the reservoir 10 will loe below, and the center of the discharge opening 'il will coincide with the axis ll, and so that the crucihle may loe freely slid to and fro on the platform, along the line ot' the axis E.

The cross-bean'l 2 is formed at its other end with a counter-weight 12. Removably supported on the upper edges ot the cradle 3 and concentric therewith. is an auxiliary cradle i3, having lateral arms ll and downturned flanges 15 at their outer ends to control the'auxiliary cradle 13 so that the axis of its semi-cylindrical portion will coincide with the axis l @ne of the flanges l5 is provided with a nger'piece 16 whereby the auxiliary cradle may he grasped and removed as may loc desired.

Referring to Fig'. 2 of the drawings, l have shown one of a plurality ot mold rings 17 lying in the main cradle 3 and fitting loosely therein, lthe longitudinal axis of both, coinciding and registerin;- with the discharge opening in the cruciblc. Shown in dotted lines in the same View are two auxiliary rradles 13 and lila ot varying size (of which there may he any number) all registering centrally, with the Crucible opening l1.

The cross-heam i?, together with the mold ringr and cradle poised as a unit, through the medium of stud 18, on actuating devices. (not shown) said stud being rigidly secured on the cross-beam Q. y y

To maintain an even balance in the whole rotating demone-regardless of the use of any et the interrhageablemold rings and :'cradles are made ot proportionately thicker metals (shown in Fig. 4) to compensate in weight for the variations in size.

ln use, when a large mold is required, the ring containing" the ,mold (Fig. 2) is placed in the main cradle il and the crucilole with its discharge opening is slid against it;

rllhe nie-tal in the crucible reservoir is now melted by the usual use of a yblovvpipe, when the whole device is rapidly rotated in a horizontal plane (the wall 4 sustaining the rnold ring) and the molten metal projected, by centrifugal force through the discharge openinp; 1l into the mold recesses.

The molds are formed by casting the investment material C into the mold ring around a. pattern made ot' wax. When the ed out of the mold. f

cast is thoroughly dry. intense -heat is applied wherethrough the wax pattern ie meltunity.

When an unnef arily large mold ring is used for a very en'iall casting, itrequires eonsiderable time to euiiieiently heat the large mass of material, which infrequently de- -yelops racks (Fig. A(i), because of its excessive thickness around the mold cavity.

Obviously the advantage ot" a centrifugal mold machine, wherein several sizes of mold rings may be used, is therefore very important.

To salvage metal escaping thrmigh cracks in mold (Fig. G) l provide an annular flange 19 on the outer wall ll., whereby the escaping metal is detained until cooled.

I claim:

l. ln a Centrifugal element, of a dental casting; machine, in eomliinal/ion with the cross beam and its eounterweigl'it, of a main mold ring carrier haring` an arcuate bottom and integral with said cross beam and oppo site aid counrern'eight, and an auxiliary mold ri ng carrier haring an a reuate bottom. of smaller curvature than said first, named mold carrier and eoneentrie with the bottom of the latter and removably resting thereon.

In. a centrifugal element for dental ranting maritimes. the (.ombinatiou with the' cross beam and its eounterweight, of a main semi-eylindrieal open top mold ring cradle on said cross beam and ha ring its longitudinal axis parallel tliierewith and an auxiliary open top mold ring Cradle ineertible from` above downwardly to loosfely and slidably restI ien the upper edge of said main -mold ring cradle and having its longitudinal axis coincide with the axis of the latter for the purpose specified.

3. In a centrifugal element for a dental casting machine; in combination with the cross beam. of a counter-Weight rigidly fixed at one end of the cross beam and a main comparatively large open top mold ring supi'ort adapted to hold a mold ring rigidly ixed at the opposite end ot said erossbeam.

a support between the ends ofthe cross beam arranged thereon to effect a state of equi-Y librium therein, when therev is a mold in said main mold ringr support, and a smaller auX- iliary mold ring support adapted to hold a smaller mold than said main mold ring support and loosely and removably resting on the latter, said auxiliary mold ring support.

being o proportioned in Weighty as to maintain said state of equilibrium in the cross beam when the larger mold is removed from aid main mold ring supporband theauxiliaryI mold ring support holdingI the smaller mold is inserted.

fl. In a centrifugal element for a dental casting machine. in combination with a one piece counter-balanced cross beam supported between ite ende comprising a cradle oppo- `site the eounterweight and adapterlto hold ay mold of certain weight removably fitting Said cradle, said cross beam being in a state of equilibrium on its support when supporting said mold, and an independent cradle inleertible in said first named cradle and adapted to contain a mold of lesser Weight'than Said first named mold, the combined Weight sertible in the open top of the -irst named mold ring support and removably resting thereon.

In testimony 'whereof I affix my signature in presence of tivo Witnesses. I

.DAVID PERRY. fWitnesseS: 'i y' H. S. JOHNSON; i Geenen VOELKER. 

